/*
 * Copyright 2017 ABSA Group Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package za.co.absa.spline.common.transformations

import scala.collection.mutable

trait AbstractConverter {
  type From
  type To

  def convert(arg: From): To
}

trait CachingConverter extends AbstractConverter {
  private val cache = mutable.LinkedHashMap.empty[From, To]

  def values: Seq[To] = cache.values.toSeq

  abstract override def convert(arg: From): To =
    cache.getOrElseUpdate(arg, super.convert(arg))
}

